Various types of photoacoustic sensors are known to detect gases. These include, Fritz et al., U.S. Patent Application No. 2009/0320561, published Dec. 31, 2009 and entitled “Photoacoustic Cell”; Fritz et al., U.S. Patent Application No. 2010/0027012, published Feb. 4, 2010 and entitled, “Photoacoustic Spectroscopy System”; Fritz et al., U.S. Patent Application No. 2010/0045998, published Feb. 25, 2010 and entitled “Photoacoustic Sensor”. The above noted published applications have been assigned to the assignee hereof, and are incorporated herein by reference.
Such sensors, while useful, can be affected by thermally generated noise. Such noise can create errors in output signals indicative of ambient sensed gas.